It is desirable for the interior of many enclosures to be maintained at a controlled humidity. For example, in the context of electronics enclosure, maintaining a low humidity can have the benefit of avoiding corrosion and deterioration of the electronic components caused by water molecules, but maintaining too low humidity in the electronics enclosure can lead to static electricity, which can damage components. As such, it is often desirable to control the humidity within particular relative humidity ranges. For example, in the case of disk drive enclosures, the amount of water vapor within the disk drive enclosure can affect air density, thereby impacting the fly height of read-write heads. In these situations it is desirable to keep a controlled, consistent humidity so that the read-write head height can be kept within specific narrow ranges. This is particularly significant in the context of a sealed enclosure, where the amount of moisture in the adsorbent will be permanently trapped within the enclosure.
Adsorbent assemblies are typically used in enclosures to control humidity, which can contain various adsorbent materials such as silica gel, activated carbon, and the like. However, the mere addition of an adsorbent into a disk drive enclosure (as an example) does not necessarily solve all the water control problems because of various factors such as the manner in which the water is adsorbed and desorbed during the production, storage, and operation of the disk drive. The challenge of controlling humidity within an enclosure is compounded by the variable conditions in which the adsorbent assemblies and the enclosures themselves are manufactured: many manufacturing settings are in relatively open environments where any adsorbent that is present can readily absorb atmospheric moisture. Therefore, a need exists for controlling and maintaining the water content in the adsorbent assembly during manufacturing and handling so that the desired humidity level of the adsorbent assembly and, therefore, the enclosure, can be maintained.